1. Field of the Invention
The present invention relates to a monitoring device, a monitoring method, and a monitoring program, and more particularly, to a monitoring device, a monitoring method, and a monitoring program for detecting/identifying a suspicious person.
2. Description of the Related Art
Recently, devices for monitoring suspicious persons have been employed to detect suspicious persons in detection areas, and, upon detection, to issue an alarm/notice of the existence thereof. A related technology is disclosed in Japanese Patent Application Laid-open No. 2005-284370. A security system described in Japanese Patent Application Laid-open No. 2005-284370 detects a person (object) in a detection area by means of a human detection sensor. Moreover, this security system according to Japanese Patent Application Laid-open No. 2005-284370 reads an identification (ID) number of an IC tag using an IC tag reader, and collates the read ID number to registered ID numbers. Then, when the read ID number is registered, this security system according to Japanese Patent Application Laid-open No. 2005-284370 does not generate an alarm (such as sound)/notice. In other words, when an ID number cannot be read (cannot be received by IC tag reader) or when the read ID number is not registered, this security system generates an alarm (such as sound)/notice of the existence of a suspicious person. This security system according to Japanese Patent Application Laid-open No. 2005-284370 recognizes a person without carrying an IC tag or a person carrying an invalid IC tag as a suspicious person.
Japanese Patent Application Laid-open No. 2006-79236 discloses a system, which is intended to be installed at a common entrance of a housing complex, for identifying residents thereby providing information thereon for managing passers-by. This system according to Japanese Patent Application Laid-open No. 2006-79236 determines whether or not a passer-by is a resident at the part used by the residents in common of the housing complex, unlocks the entrance, and confirms an entrance of a person who is not a resident to the housing complex. As a result, the system according to Japanese Patent Application Laid-open No. 2006-79236 can increase security at the part used by the residents in common.
A first problem with the security system according to Japanese Patent Application Laid-open No. 2005-284370 is that a suspicious person cannot be detected because, even when a person without an IC tag is detected in the detection area and the alarm/notice is thus generated, once a permitted person with an IC tag with a registered ID number enters the detection area, the alarm/notice stops while the suspicious person still exists. This is because this security system according to Japanese Patent Application Laid-open No. 2005-284370 determines that a person has the permission based only on the fact that an ID number of an IC tag read by the IC tag reader upon detection of a person (object) by the human detection sensor is registered, and determines that a person without a registered ID number is a suspicious person.
A second problem with this security system according to Japanese Patent Application Laid-open No. 2005-284370 is that, once the alarm/notice stops, when security staff rush to the detection area and a plurality of persons exist in the detection area, it is not possible to determine whether or not the plurality of persons include the suspicious person. Moreover, this security system according to Japanese Patent Application Laid-open No. 2005-284370 has a problem that, when there are the suspicious person and at least one permitted person in the detection area, and then, the suspicious person leaves the detection area, the security staff cannot distinguish the suspicious person. In other words, this security system according to Japanese Patent Application Laid-open No. 2005-284370 has a problem that it is hard for the security staff to identify a suspicious person by actually observing the detection area. This is because this security system according to Japanese Patent Application Laid-open No. 2005-284370 carries out an alarm/notice only based on the information on whether or not a suspicious person exists, but does not provide information for identifying the suspicious person.
Moreover, though the system according to Japanese Patent Application Laid-open No. 2006-79236 can be used to confirm that a person other than the residents enters the housing complex, and to confirm that a person who is passing by the sensor is a non-resident, there is a problem that the system does not offer a function of continuously monitoring a suspicious person.
These problems possibly happen frequently in a crowded corridor, lobby, or the like.